15.2v charging seems a bit high while driving

[mav47]

The BMS determines when the 12V Battery is charging. It is not a constantly charging.

When you see the 15.2V you cannot make the assumption that the BMS is charging the battery with that voltage.

I am not making that assumption: I measured at the battery terminals and compared it to the reading of my in-dash voltage meter in the DC plug. The difference between both readings never exceeded 0.1V, so my dash voltage meter reading equals battery terminal voltage.

And to me this makes sense: the 12V battery is directly tied into the 12V system in the vehicle and the BMS appears to set the system (=charging) voltage coming from the DC-DC converter. (or the alternator on ICE vehicles).

The BMS keeps track of the battery's State of Charge (SOC) by reading current IN vs current OUT through the current sensor that connects the battery negative terminal to the ground. Which is why you need to "reset" the BMS when you install a new battery. I understand the default SOC target to be between 60 and 80%.

In the end, the BMS simply controls charging current into the battery by changing the system voltage with a likely cap somewhere in the mid 15V range.

Once the SOC target is reached, the BMS will lower the system voltage so the battery does not take charging current anymore.

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[mav47]

Mav47, keep us posted on how the AMG battery does. I plan to replace my hybrid battery with a AMG when needed. Can you share the AMG battery model you purchased?

In these forums I did not find a single "GROUP TYPE" for the proper battery in the Maverick Hybrid. Various owners put an H5 type battery in their Hybrid, but had to cut off two tabs that keep the battery in place. I didn't like that idea as I feel the battery should be safely held in case of collisions, etc.

Someone in this forum (sorry, cannot find the post, otherwise I'd link it) posted a link to this website, which was helpful.

As it turns out, after measuring the proper battery size for the Maverick Hybrid is:

GROUP 140R (=BCI code, most common in US)
LN1 (seems to be a Yuasa Japanese code)
H4 (DIN code, so European designation)

And it bolts right in.

I found that 50Ah AGM versions of this battery type listed around 570CCA and 80RC (=reserve capacity, which is likely more important for the hybrid than CCA)

Compare that to the OEM flooded chemistry battery that came with the truck: 45Ah, 65RC.

I bought one of these Group 140R/LN1/H4 UPLus AGM batteries on Amazon: https://www.amazon.com/dp/B0CM3GZWXX?th=1, but do note that they only showed Qty 20 in stock and now they don't show H4 as available anymore (only H5, H6 are currently listed, but that may change again). Was a bit of a gamble, but the company behind these batteries is a big one so I thought I'd try it for $134 minus a 10% coupon and including shipping. Most all these AGM batteries are made overseas anyways, I think you can have just as much good or bad luck with a better known brand one.

That UPlus battery came shipped in GREAT packaging, well protected and seems well made. I think it will be fine.

An alternative I looked at is that LN1 AC Delco that was listed above by @uga , also at RockAuto https://www.rockauto.com/en/moreinfo.php?pk=8878472

I think you likely cannot go wrong as long as you buy a battery of this group 140R size and as long at it is an AGM battery.

I'll post if my luck with this UPlus battery changes

 

[AzureBlueBill]

Hook up a volt meter to almost any properly operating 12 volt car/truck. You'll usually see around 15 volts when it is running. Been this way almost forever.

 

[Builder]

Great info and interesting read; puts my mind somewhat at ease regarding the 15.2v read. I’ll stick with the OEM 12v until I can’t. I’ll probably put an AGM in sooner rather than later based on the experiences within the MTC. This whole 12v battery issue is frustrating and should have been addressed by Ford by now. Thanks for all the input.

 

[Darnon]

I am not making that assumption: I measured at the battery terminals and compared it to the reading of my in-dash voltage meter in the DC plug. The difference between both readings never exceeded 0.1V, so my dash voltage meter reading equals battery terminal voltage.

And to me this makes sense: the 12V battery is directly tied into the 12V system in the vehicle and the BMS appears to set the system (=charging) voltage coming from the DC-DC converter. (or the alternator on ICE vehicles).

Yeah, there's nothing between the DC-DC converter and the battery that'd be further controlling the voltage/current. It's literally DC-DC converter > cable > 300A fuse > underhood junction box bus bar > battery cable (infamous for the soldered terminal failing) > 200A fuse at batt+ terminal > battery.

Also I know it's getting 15+ volts at the battery because that's where I tie in my amplifiers and had trouble with some going into overvoltage protection. Strangely, opening a door triggers it dropping the voltage commanded down.

Another quirk I noticed recently is that Key On but not Ready ('started') the DC-DC converter does seem to output some voltage; was seeing about 12.9V. I was under the impression that the HV contactor would be open still in that state, unless it's utilizing power from the pre-charge circuit?

 

[mav47]

Just spotted the same exact battery as that UPlus, but now with a different brand name. Ships from the same seller too:

MARXON Group 140R H4 LN1 Start and Stop Car Battery 12v 50AH 570CCA AGM BCI140R Maintenance Free Automotive Replacement Batteries https://a.co/d/i3N9F0J

Edit: now seems sold out too.

 

[MakinDoForNow]

Yeah, there's nothing between the DC-DC converter and the battery that'd be further controlling the voltage/current. It's literally DC-DC converter > cable > 300A fuse > underhood junction box bus bar > battery cable (infamous for the soldered terminal failing) > 200A fuse at batt+ terminal > battery.

Also I know it's getting 15+ volts at the battery because that's where I tie in my amplifiers and had trouble with some going into overvoltage protection. Strangely, opening a door triggers it dropping the voltage commanded down.

Another quirk I noticed recently is that Key On but not Ready ('started') the DC-DC converter does seem to output some voltage; was seeing about 12.9V. I was under the impression that the HV contactor would be open still in that state, unless it's utilizing power from the pre-charge circuit?

With key on but not Ready the contactor is closed and DCDC convertor is providing current (a screen may pop up showing extended auxillary power active or something similar) until the HVB SOC drops to 30-32% (don't remember which). It's possible the 12v time delay will turn off the auxillary power before the HVB drops to the cut off voltage.

 

[peekaypee]

The stock battery in the Hybrid is a flooded cell battery, NOT an AGM, even though the settings in the vehicle are supposedly for an AGM battery. Note that comparable Toyota planetary gear hybrids all come standard with AGM batteries.

Word is that Ford has been unable to source enough AGM batteries, so they ended up putting flooded batteries in the Maverick Hybrids. Or it was simply a matter of cost as I understand they're still putting flooded batteries in these trucks.

Lots of Hybrid owners have reported deep sleep trouble caused by under voltage, which supposedly goes away after replacing the stock battery with an AGM. This to me indicates that this vehicle should have had an AGM battery in the first place.

After getting some deep sleep messages I played a bit with ForScan and changed the settings for the BMS (battery management system) from 80% state of charge to 95% state of charge (SOC). The system voltages never changed. It didn't seem to make a difference: I still got the occasional deep sleep.

Similar to the OP, a few weeks ago I put a voltage meter display in that same 12V plug and I noticed the same: system voltages between 14.8 (rare) and 15.1 (most of the time). I've seen 15.2V too! That seemed wild to me.

So yesterday I bit the bullet and installed a new Group 140R AGM battery. I also reset the BMS.

As others reported when replacing their flooded battery with an AGM: the system voltage instantly dropped to more "normal" values well below 15V!

Edit 4: with a few hundred miles on this new battery I have been seeing voltages between 14.6-14.8, right after startup and then after a while it drops down to 13.0V. Occasionally it will charge for a longer time steadily at at 14.6V. Seems to me that all is well.


Here's what I think happens on these Hybrids:

1) My abused (chronically undercharged) OEM flooded battery likely has too high an internal resistance, which means that it will accept fewer charging amps at any given voltage. This battery was probably always below its target SOC and the BMS tries to bring the SOC up by feeding it charging current, and it raises the voltage to get there (north of 15.0V). Essentially the BMS was ALWAYS charging the battery, and that's exactly what I observed: voltages always showing between 14.9 and 15.2V, likely still too low for a solid charging current to get the battery up to the required SOC.

2) The new AGM battery has a much lower internal resistance (lower even than a brand new flooded battery), and will take a significant charging current already at much more "normal" voltages: I'm typically seeing 14.6-14.8 when it is charging. Once the BMS determines the battery has reached the required SOC level, it drops the system voltage to 13.0V which means the battery does not charge anymore.

I'll keep an eye on it over the coming months, but I suspect that the deep sleep troubles are over.

Again: this vehicle should have had an AGM battery in the first place.

Edit 5, three months, and about 6,000 miles later: Indeed, the random deep sleep issues are completely gone, and the system voltages stay between 14.6 and 14.8V, dropping to 13.0V once the battery reaches its target SOC. Seems fine to me.

I've had ONE occasion where the truck reported going to deep-sleep, and that was after being parked for 16 days while we were on a family vacation. I consider that fine as that's what this deep sleep feature is for. Interestingly: when I first turned on the truck after 19 days it started charging at 15.2V for the first 10 min or so, then dropped to its normal 14.6-14.8V. That was the only time I've ever seen over 15V on the system with this AGM battery , and must have been due to a lower than normal SOC.

Good morning Mav47. My name is Paul and I appreciateed your right up and experience with this issue. I have a 22 hybrid lariat and have been having this issue off and on. Ford replaced the battery and other things done but it has gone back to the deep sleep mode pretty frequently. I don't understand quite all the technical stuff that you listed, but I believe you were thorough. Now that it's into the end of May, how is everything going with your replacement? Would you possibly be able to specify which battery you put in specifically? And was there any modifications to install this new aftermarket battery? And finally, was there any re-programming you had to do using Forscan or other techniques?
Thank you so much ahead of time and I look forward to your reply if you're able to. My best to you

 

[mav47]

Good morning Mav47. My name is Paul and I appreciateed your right up and experience with this issue. I have a 22 hybrid lariat and have been having this issue off and on. Ford replaced the battery and other things done but it has gone back to the deep sleep mode pretty frequently. I don't understand quite all the technical stuff that you listed, but I believe you were thorough. Now that it's into the end of May, how is everything going with your replacement? Would you possibly be able to specify which battery you put in specifically? And was there any modifications to install this new aftermarket battery? And finally, was there any re-programming you had to do using Forscan or other techniques?
Thank you so much ahead of time and I look forward to your reply if you're able to. My best to you

Good afternoon, fellow San Diegan!

I saw that someone quoted my older post about this issue yesterday, so I had just updated it with my experience 6,000 miles after installing that AGM battery.

In a nutshell: The random deep sleep troubles are completely gone since installing that AGM battery. And as I've been keeping an eye on the voltage using my in-dash voltage meter, it performs exactly as I'd expect it to.

I did keep the BMS SOC target set to 95% in ForScan (I didn't touch it after fiddling with the settings well before replacing that battery). But at this point I'm willing to bet that if you don't touch it and keep the SOC setting at the stock 80% you'd have no problems either. So don't worry about it.

Battery type you need for the Maverick Hybrid:

GROUP 140R (=BCI code, most common in US)
LN1 (seems to be a Yuasa Japanese code)
H4 (DIN code, so European designation)

They're just different identifiers for the same exact size battery. And this is an exact match and drops right in.

Make SURE it is an AGM battery though, as in this type (Group 140R/LN1/H4) you can get either flooded or AGM. Most will be AGM, but I remember seeing some flooded ones on offer.

The exact battery that I bought is not available anymore. (some wonky brand "UPLUS", but like all these AGMs it came from a large Chinese manufacturer so should be fine).

This Group 140R/LN1/H4 battery type is kind of hard to find which surprised me. Most places will offer the much more common H5 AGM battery, which will also fit in the Maverick Hybrid, but you will need to cut off some tabs in the battery tray because the H5 is longer than the properly fitting H4. I didn't like that idea.

I just did some quick searches for an H4/LN1/Group140R AGM battery again. One battery that keeps popping up and should be correct is this one:

https://www.amazon.com/ACDelco-LN1AGM-Month-Warranty-Battery/dp/B004GJ8DEQ

And another one, which may actually be the same battery:

https://www.amazon.com/ACDelco-LN1AGM-Professional-Automotive-Battery/dp/B010GJ4EZQ

These AC Delco's appear to be the stock 12V AGM battery for the Chevrolet Bolt EV. I'd pick any of these if you cannot find a cheaper off-brand one.

Good luck!

 

[peekaypee]

Good afternoon, fellow San Diegan!

I saw that someone quoted my older post about this issue yesterday, so I had just updated it with my experience 6,000 miles after installing that AGM battery.

In a nutshell: The random deep sleep troubles are completely gone since installing that AGM battery. And as I've been keeping an eye on the voltage using my in-dash voltage meter, it performs exactly as I'd expect it to.

I did keep the BMS SOC target set to 95% in ForScan (I didn't touch it after fiddling with the settings well before replacing that battery). But at this point I'm willing to bet that if you don't touch it and keep the SOC setting at the stock 80% you'd have no problems either. So don't worry about it.

Battery type you need for the Maverick Hybrid:

GROUP 140R (=BCI code, most common in US)
LN1 (seems to be a Yuasa Japanese code)
H4 (DIN code, so European designation)

They're just different identifiers for the same exact size battery. And this is an exact match and drops right in.

Make SURE it is an AGM battery though, as in this type (Group 140R/LN1/H4) you can get either flooded or AGM. Most will be AGM, but I remember seeing some flooded ones on offer.

The exact battery that I bought is not available anymore. (some wonky brand "UPLUS", but like all these AGMs it came from a large Chinese manufacturer so should be fine).

This Group 140R/LN1/H4 battery type is kind of hard to find which surprised me. Most places will offer the much more common H5 AGM battery, which will also fit in the Maverick Hybrid, but you will need to cut off some tabs in the battery tray because the H5 is longer than the properly fitting H4. I didn't like that idea.

I just did some quick searches for an H4/LN1/Group140R AGM battery again. One battery that keeps popping up and should be correct is this one:

https://www.amazon.com/ACDelco-LN1AGM-Month-Warranty-Battery/dp/B004GJ8DEQ

And another one, which may actually be the same battery:

https://www.amazon.com/ACDelco-LN1AGM-Professional-Automotive-Battery/dp/B010GJ4EZQ

These AC Delco's appear to be the stock 12V AGM battery for the Chevrolet Bolt EV. I'd pick any of these if you cannot find a cheaper off-brand one.

Good luck!

Awesome information!! Thank you so much for taking the time and elaborate. I'm definitely going to have to pick up one of these batteries. I don't have forscan or know anything on how to do it, but I'll go that route you mentioned of just putting the battery in and seeing how it works.
By the way, are you also here in San Diego? I'm out here in the San Carlos area of San Diego.
Thanks again my friend! I really appreciate it!

 

[uga]

Excellent info mav47

How about $151 to $155 for a AGM Battery

https://www.rockauto.com/en/moreinfo.php?pk=8878472&cc=0&pt=2476&jsn=4

https://www.summitracing.com/parts/...W1gD2V129Ydob19I2jhg7c_1BPTDD5KcaAi23EALw_wcB

 

[MaveRichard]

[/QUOTE]

The stock battery in the Hybrid is a flooded cell battery, NOT an AGM, even though the settings in the vehicle are supposedly for an AGM battery. Note that comparable Toyota planetary gear hybrids all come standard with AGM batteries.

Word is that Ford has been unable to source enough AGM batteries, so they ended up putting flooded batteries in the Maverick Hybrids. Or it was simply a matter of cost as I understand they're still putting flooded batteries in these trucks.

Lots of Hybrid owners have reported deep sleep trouble caused by under voltage, which supposedly goes away after replacing the stock battery with an AGM. This to me indicates that this vehicle should have had an AGM battery in the first place.

After getting some deep sleep messages I played a bit with ForScan and changed the settings for the BMS (battery management system) from 80% state of charge to 95% state of charge (SOC). The system voltages never changed. It didn't seem to make a difference: I still got the occasional deep sleep.

Similar to the OP, a few weeks ago I put a voltage meter display in that same 12V plug and I noticed the same: system voltages between 14.8 (rare) and 15.1 (most of the time). I've seen 15.2V too! That seemed wild to me.

So yesterday I bit the bullet and installed a new Group 140R AGM battery. I also reset the BMS.

As others reported when replacing their flooded battery with an AGM: the system voltage instantly dropped to more "normal" values well below 15V!

Edit 4: with a few hundred miles on this new battery I have been seeing voltages between 14.6-14.8, right after startup and then after a while it drops down to 13.0V. Occasionally it will charge for a longer time steadily at at 14.6V. Seems to me that all is well.


Here's what I think happens on these Hybrids:

1) My abused (chronically undercharged) OEM flooded battery likely has too high an internal resistance, which means that it will accept fewer charging amps at any given voltage. This battery was probably always below its target SOC and the BMS tries to bring the SOC up by feeding it charging current, and it raises the voltage to get there (north of 15.0V). Essentially the BMS was ALWAYS charging the battery, and that's exactly what I observed: voltages always showing between 14.9 and 15.2V, likely still too low for a solid charging current to get the battery up to the required SOC.

2) The new AGM battery has a much lower internal resistance (lower even than a brand new flooded battery), and will take a significant charging current already at much more "normal" voltages: I'm typically seeing 14.6-14.8 when it is charging. Once the BMS determines the battery has reached the required SOC level, it drops the system voltage to 13.0V which means the battery does not charge anymore.

I'll keep an eye on it over the coming months, but I suspect that the deep sleep troubles are over.

Again: this vehicle should have had an AGM battery in the first place.

Edit 5, three months, and about 6,000 miles later: Indeed, the random deep sleep issues are completely gone, and the system voltages stay between 14.6 and 14.8V, dropping to 13.0V once the battery reaches its target SOC. Seems fine to me.

I've had ONE occasion where the truck reported going to deep-sleep, and that was after being parked for 16 days while we were on a family vacation. I consider that fine as that's what this deep sleep feature is for. Interestingly: when I first turned on the truck after 19 days it started charging at 15.2V for the first 10 min or so, then dropped to its normal 14.6-14.8V. That was the only time I've ever seen over 15V on the system with this AGM battery , and must have been due to a lower than normal SOC.

It seems to me like you may have actually, definitively, figured this out.

My one question really is this and it is completely out of ignorance - could you, in ForScan, change the battery type to flooded?

 

[uga]

Yes, but no idea if that will make a difference....................................

 

[Tom201326]

The stock battery in the Hybrid is a flooded cell battery, NOT an AGM, even though the settings in the vehicle are supposedly for an AGM battery. Note that comparable Toyota planetary gear hybrids all come standard with AGM batteries.

Word is that Ford has been unable to source enough AGM batteries, so they ended up putting flooded batteries in the Maverick Hybrids. Or it was simply a matter of cost as I understand they're still putting flooded batteries in these trucks.

Lots of Hybrid owners have reported deep sleep trouble caused by under voltage, which supposedly goes away after replacing the stock battery with an AGM. This to me indicates that this vehicle should have had an AGM battery in the first place.

After getting some deep sleep messages I played a bit with ForScan and changed the settings for the BMS (battery management system) from 80% state of charge to 95% state of charge (SOC). The system voltages never changed. It didn't seem to make a difference: I still got the occasional deep sleep.

Similar to the OP, a few weeks ago I put a voltage meter display in that same 12V plug and I noticed the same: system voltages between 14.8 (rare) and 15.1 (most of the time). I've seen 15.2V too! That seemed wild to me.

So yesterday I bit the bullet and installed a new Group 140R AGM battery. I also reset the BMS.

As others reported when replacing their flooded battery with an AGM: the system voltage instantly dropped to more "normal" values well below 15V!

Edit 4: with a few hundred miles on this new battery I have been seeing voltages between 14.6-14.8, right after startup and then after a while it drops down to 13.0V. Occasionally it will charge for a longer time steadily at at 14.6V. Seems to me that all is well.


Here's what I think happens on these Hybrids:

1) My abused (chronically undercharged) OEM flooded battery likely has too high an internal resistance, which means that it will accept fewer charging amps at any given voltage. This battery was probably always below its target SOC and the BMS tries to bring the SOC up by feeding it charging current, and it raises the voltage to get there (north of 15.0V). Essentially the BMS was ALWAYS charging the battery, and that's exactly what I observed: voltages always showing between 14.9 and 15.2V, likely still too low for a solid charging current to get the battery up to the required SOC.

2) The new AGM battery has a much lower internal resistance (lower even than a brand new flooded battery), and will take a significant charging current already at much more "normal" voltages: I'm typically seeing 14.6-14.8 when it is charging. Once the BMS determines the battery has reached the required SOC level, it drops the system voltage to 13.0V which means the battery does not charge anymore.

I'll keep an eye on it over the coming months, but I suspect that the deep sleep troubles are over.

Again: this vehicle should have had an AGM battery in the first place.

Edit 5, three months, and about 6,000 miles later: Indeed, the random deep sleep issues are completely gone, and the system voltages stay between 14.6 and 14.8V, dropping to 13.0V once the battery reaches its target SOC. Seems fine to me.

I've had ONE occasion where the truck reported going to deep-sleep, and that was after being parked for 16 days while we were on a family vacation. I consider that fine as that's what this deep sleep feature is for. Interestingly: when I first turned on the truck after 19 days it started charging at 15.2V for the first 10 min or so, then dropped to its normal 14.6-14.8V. That was the only time I've ever seen over 15V on the system with this AGM battery , and must have been due to a lower than normal SOC.

Hey mav47!

I also have my battery replaced with an AGM battery. Unfortunately, Deep Sleep still occur, with my car lasting barely a week before FordPass notify me. How often do you use your truck?

- Khoa

 

[maggy55]

I replaced my OEM battery with a higher capacity AGM. After replacement no deep sleep. When charging the voltage is around 14.5, before it was 15v something. Seems like it was a good decision.

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